Chuck



Dec. 8, 1936. w. H. SCHNEIbER CHUCK Filed March 5, 1955 INVENTOR QM 7 I Patented be... 8, 1936 2,063,344

. UNITED STATES PATENT OFFHEE CHUCK William Henry Schneider, Pittsburgh, Pa.

Application March 5, 1935, Serial No. 9,379

2 Claims. (Cl. 279-72) My invention relates to chucks, and is hereinof rollers I5 that function as gripping elements after described as of a type particularly suitor clutch members for engagement with the able for use in connection with small tools such shank of a tool I6 that is inserted into a central as dentists drills, grinders, reamers, taps, and opening in the end of the shaft II.

5 the like, but various features thereof are capable The sleeve 44 has a cam surface I! formed 5 of use in connection with various other classes on its inner wall for each of the rollers 15. It of work. Will be seen that when the rollers I5 are moved One object of my invention is to provide a in either direction from the center of the cam chuck of such form that tools may be consurfaces I I, in the sleeve I4, that they will be 10 veniently applied to and removed therefrom, brought into gripping engagement with the tool 10 without the necessity of stopping the shaft which shank I6, so that the tool will rotate with the drives the chuck. shaft It. The tension of the spring 92 is such Another object of my invention is to provide that the parts will normally be maintained in an improved means whereby the chuck can be tool-gripping position.

5 conveniently held by the operator and readily An important feature of my invention con manipulated to effect engagement and disensists in having the cam surfaces ll each formed gagement of the tools. throughout its length on an arc of constant A further object of my invention is to provide radius, so that the rollers will be held in gripa chuck of the roller or ball type that can be ping engagement with the tool at either of the readily changed for use with drive shafts that opposite positions of the rollers on said camrotate in different directions. ming surfaces.

Still another object of my invention is to The spring I2 can be reversed so as to cause provide a chuck of the type referred to, wherethe sleeve I4 to move in a clockwise direction in the eccentric seats and rolling surfaces for from the position indicated in Fig. 4, so that the balls or rollers can be more quickly and acif the shaft I I is driven in the direction oppo- 25 curately formed than in the case of various site to that indicated by the arrow in Fig. 2, the previously-known types of chucks. tool I6 will be properly gripped by the rollers One form which my invention may take is I5. This feature is of particular utility as it shown in the accompanying drawing wherein will permit of the chuck being employed with Figure l is a longitudinal sectional view of the shafts driven in either direction. 30 chuck; Fig. 2 is a view taken on the line IIII Also, the camming surfaces I! can be more of Fig. 1; Fig. 3 is a view taken on the line readily and accurately formed since they re- IIIIII of Fig. 1; Fig. 4 is a view similar to that quire machining by only a single tool of a proper of Fig. 2, but showing the chuck parts in re radius, and thus avoiding the more difficult leased position; Fig. 5 is a side view of a poroperation of forming camming surfaces along 35 tion of the apparatus of Fig. 1; Fig. 6 is an lines which are of constantly changing radius. end view thereof; Fig. 7 is a longitudinal sec- A closure plate I8 is provided for the end of tional view of the clutch sleeve of Fig. 1, and the chuck sleeve l4, and is inserted in an an- Fig. 8 is a View of the end plate for the clutch nular recess formed in the said sleeve, the end sleeve. of the sleeve being peened down to securely hold 40 A portion of a holder whereby the operator the plate in place. The plate serves as an end may hold the chuck is represented by the stop to prevent the sleeve I4 from slipping rearnumeral I0, which holder may suitably be of wardly on the shaft II, and also to close the sleeve-like form and through which extends a front of the chuck against the entrance of grit shaft II that may be driven from a suitable and dirt. 45 source of power, such as an electric motor. In A sleeve-like extension 20 is carried by the the case of dental tools, the shaft II would be holder I0, and carries a brake button 2| that driven from a flexible shaft. may be pushed into engagement with the chuck The shaft II is provided With a peripheral sleeve I4, in order to retard rotative movement slot to the innermost wall of which is secured an of the sleeve I4, and cause further rotative 50 end of a spring I2. The other end of the spring movement of the shaft II to contract the spring I2 has connection with the inner end of a screw I2 and move the rollers I5 to the position shown I3 which has threaded engagement with a chuck in Fig. 4, where they will no longer have gripsleeve I4. The forward end of the shaft II is ping engagement with the tool shank I6.

66 reamed out to form recesses for the reception At such position of the parts, the shaft can continue to rotate, and at the same time, the tool l6 can be removed and another tool inserted. Upon release of the button 2 I, the spring l2 will again expand to move the sleeve [4 forwardly relative to the shaft l I, to the position shown in Fig. 2. If the position of the spring as shown in Fig. 3 is reversed, the sleeve M will be moved to a position the reverse of that shown in Fig. 2, so as to cause gripping engagement with the tool when the shaft is driven in the opposite direction.

The sleeve-like extension 20 not only affords a convenient means for supporting the brake button, but enables the operator to hold the chuck without danger of his hands coming into contact with rotating parts of the apparatus. However, the handle and the sleeve 20, together with the brake button 2|, can be eliminated, and the shaft ll otherwise suitably supported, in which case release of the chuck elements would be effected by the operator simply pressing his thumb or fingers on the chuck sleeve 14 to cause contraction of the spring [2 during continued rotation of the shaft I l relative to the sleeve I4.

I claim as my invention:-

1. The combination with a chuck shaft, of a cage carried by the forward end of the shaft and having radially extending openings, gripping elements loosely fitting within said openings and arranged to grip a tool shank which is positioned centrally of the cage, an oscillatory chuck sleeve encircling the cage, and provided with camming means for forcing the said gripping elements inwardly into gripping engagement with a tool shank, at either of two opposite rotative positions of the sleeve, a spring connected to the chuck sleeve and the shaft, and serving to normally yieldably hold the sleeve with the backwardlyextending camming surface of each camming means in engagement with its associated gripping element, when the chuck shaft is to be driven in one direction, the said spring being reversible to so hold the sleeve that its other camming surfaces engage said gripping elements when the chuck shaft is to be driven in the opposite direction, a stationary handle for the chuck, positioned adjacent to the said sleeve, and a braking device carried by said handle for movement into engagement with the said sleeve to retard movement thereof and cause retraction of the sleeve through continued rotation of the chuck shaft, said'spring limiting retractive movement of the sleeve to cause release of said gripping elements.

2. The combination with a chuck shaft, of a cage carried by the forward end of the shaft and having radially-extending openings, gripping elements loosely fitting within said openings and arranged to grip a tool shank which is positioned centrally of the cage, an oscillatory chuck sleeve encircling the cage and provided with arcuate recesses opposite each gripping element, the bottom walls of the recesses being disposed on lines of a radius that is shorter than the internal radius of the sleeve at points between the said recesses, so that the ends of the recesses intersect the inner wall of the sleeve, whereby each gripping element may have cooperative camming engagement with the bottom wall of its associated recess at points toward either end of each recess, and a spring disposed around the chuck shaft and secured at its ends to the sleeve and the shaft, respectively, and serving to normally yieldably hold the sleeve in its maximum jaw-projecting position adjacent to said intersecting ends of the recesses, the sleeve being held so that the backwardly-extending camming surface of each recess is in engagement with its associated gripping element when the chuck shaft is to be driven in one direction, and the said spring being reversibly mountable on said shaft to so hold the sleeve that its other camming surfaces engage said gripping elements when the chuck shaft is to be driven in the opposite direction, the spring being of such length that when contracted the sleeve will be held with the mid-point of said recesses thereof radially opposite said gripping elements.

WILLIAM H. SCHNEIDER. 

